1 files changed, 292 insertions, 115 deletions

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index f9f77bee0b1..59ef2802fcf 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -7,7 +7,7 @@
  * Released under the GPL v2. (and only v2, not any later version)
  */
 #include "util.h"
-#include <lk/debugfs.h>
+#include <api/fs/debugfs.h>
 #include <poll.h>
 #include "cpumap.h"
 #include "thread_map.h"
@@ -18,6 +18,7 @@
 #include <unistd.h>
 
 #include "parse-events.h"
+#include "parse-options.h"
 
 #include <sys/mman.h>
 
@@ -49,6 +50,18 @@ struct perf_evlist *perf_evlist__new(void)
 	return evlist;
 }
 
+struct perf_evlist *perf_evlist__new_default(void)
+{
+	struct perf_evlist *evlist = perf_evlist__new();
+
+	if (evlist && perf_evlist__add_default(evlist)) {
+		perf_evlist__delete(evlist);
+		evlist = NULL;
+	}
+
+	return evlist;
+}
+
 /**
  * perf_evlist__set_id_pos - set the positions of event ids.
  * @evlist: selected event list
@@ -68,7 +81,7 @@ static void perf_evlist__update_id_pos(struct perf_evlist *evlist)
 {
 	struct perf_evsel *evsel;
 
-	list_for_each_entry(evsel, &evlist->entries, node)
+	evlist__for_each(evlist, evsel)
 		perf_evsel__calc_id_pos(evsel);
 
 	perf_evlist__set_id_pos(evlist);
@@ -78,7 +91,7 @@ static void perf_evlist__purge(struct perf_evlist *evlist)
 {
 	struct perf_evsel *pos, *n;
 
-	list_for_each_entry_safe(pos, n, &evlist->entries, node) {
+	evlist__for_each_safe(evlist, n, pos) {
 		list_del_init(&pos->node);
 		perf_evsel__delete(pos);
 	}
@@ -88,14 +101,18 @@ static void perf_evlist__purge(struct perf_evlist *evlist)
 
 void perf_evlist__exit(struct perf_evlist *evlist)
 {
-	free(evlist->mmap);
-	free(evlist->pollfd);
-	evlist->mmap = NULL;
-	evlist->pollfd = NULL;
+	zfree(&evlist->mmap);
+	zfree(&evlist->pollfd);
 }
 
 void perf_evlist__delete(struct perf_evlist *evlist)
 {
+	perf_evlist__munmap(evlist);
+	perf_evlist__close(evlist);
+	cpu_map__delete(evlist->cpus);
+	thread_map__delete(evlist->threads);
+	evlist->cpus = NULL;
+	evlist->threads = NULL;
 	perf_evlist__purge(evlist);
 	perf_evlist__exit(evlist);
 	free(evlist);
@@ -104,6 +121,8 @@ void perf_evlist__delete(struct perf_evlist *evlist)
 void perf_evlist__add(struct perf_evlist *evlist, struct perf_evsel *entry)
 {
 	list_add_tail(&entry->node, &evlist->entries);
+	entry->idx = evlist->nr_entries;
+
 	if (!evlist->nr_entries++)
 		perf_evlist__set_id_pos(evlist);
 }
@@ -129,7 +148,7 @@ void __perf_evlist__set_leader(struct list_head *list)
 
 	leader->nr_members = evsel->idx - leader->idx + 1;
 
-	list_for_each_entry(evsel, list, node) {
+	__evlist__for_each(list, evsel) {
 		evsel->leader = leader;
 	}
 }
@@ -152,7 +171,7 @@ int perf_evlist__add_default(struct perf_evlist *evlist)
 
 	event_attr_init(&attr);
 
-	evsel = perf_evsel__new(&attr, 0);
+	evsel = perf_evsel__new(&attr);
 	if (evsel == NULL)
 		goto error;
 
@@ -177,7 +196,7 @@ static int perf_evlist__add_attrs(struct perf_evlist *evlist,
 	size_t i;
 
 	for (i = 0; i < nr_attrs; i++) {
-		evsel = perf_evsel__new(attrs + i, evlist->nr_entries + i);
+		evsel = perf_evsel__new_idx(attrs + i, evlist->nr_entries + i);
 		if (evsel == NULL)
 			goto out_delete_partial_list;
 		list_add_tail(&evsel->node, &head);
@@ -188,7 +207,7 @@ static int perf_evlist__add_attrs(struct perf_evlist *evlist,
 	return 0;
 
 out_delete_partial_list:
-	list_for_each_entry_safe(evsel, n, &head, node)
+	__evlist__for_each_safe(&head, n, evsel)
 		perf_evsel__delete(evsel);
 	return -1;
 }
@@ -209,7 +228,7 @@ perf_evlist__find_tracepoint_by_id(struct perf_evlist *evlist, int id)
 {
 	struct perf_evsel *evsel;
 
-	list_for_each_entry(evsel, &evlist->entries, node) {
+	evlist__for_each(evlist, evsel) {
 		if (evsel->attr.type   == PERF_TYPE_TRACEPOINT &&
 		    (int)evsel->attr.config == id)
 			return evsel;
@@ -224,7 +243,7 @@ perf_evlist__find_tracepoint_by_name(struct perf_evlist *evlist,
 {
 	struct perf_evsel *evsel;
 
-	list_for_each_entry(evsel, &evlist->entries, node) {
+	evlist__for_each(evlist, evsel) {
 		if ((evsel->attr.type == PERF_TYPE_TRACEPOINT) &&
 		    (strcmp(evsel->name, name) == 0))
 			return evsel;
@@ -236,13 +255,12 @@ perf_evlist__find_tracepoint_by_name(struct perf_evlist *evlist,
 int perf_evlist__add_newtp(struct perf_evlist *evlist,
 			   const char *sys, const char *name, void *handler)
 {
-	struct perf_evsel *evsel;
+	struct perf_evsel *evsel = perf_evsel__newtp(sys, name);
 
-	evsel = perf_evsel__newtp(sys, name, evlist->nr_entries);
 	if (evsel == NULL)
 		return -1;
 
-	evsel->handler.func = handler;
+	evsel->handler = handler;
 	perf_evlist__add(evlist, evsel);
 	return 0;
 }
@@ -255,7 +273,7 @@ void perf_evlist__disable(struct perf_evlist *evlist)
 	int nr_threads = thread_map__nr(evlist->threads);
 
 	for (cpu = 0; cpu < nr_cpus; cpu++) {
-		list_for_each_entry(pos, &evlist->entries, node) {
+		evlist__for_each(evlist, pos) {
 			if (!perf_evsel__is_group_leader(pos) || !pos->fd)
 				continue;
 			for (thread = 0; thread < nr_threads; thread++)
@@ -273,7 +291,7 @@ void perf_evlist__enable(struct perf_evlist *evlist)
 	int nr_threads = thread_map__nr(evlist->threads);
 
 	for (cpu = 0; cpu < nr_cpus; cpu++) {
-		list_for_each_entry(pos, &evlist->entries, node) {
+		evlist__for_each(evlist, pos) {
 			if (!perf_evsel__is_group_leader(pos) || !pos->fd)
 				continue;
 			for (thread = 0; thread < nr_threads; thread++)
@@ -527,7 +545,7 @@ union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx)
 		if ((old & md->mask) + size != ((old + size) & md->mask)) {
 			unsigned int offset = old;
 			unsigned int len = min(sizeof(*event), size), cpy;
-			void *dst = &md->event_copy;
+			void *dst = md->event_copy;
 
 			do {
 				cpy = min(md->mask + 1 - (offset & md->mask), len);
@@ -537,7 +555,7 @@ union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx)
 				len -= cpy;
 			} while (len);
 
-			event = &md->event_copy;
+			event = (union perf_event *) md->event_copy;
 		}
 
 		old += size;
@@ -545,12 +563,19 @@ union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx)
 
 	md->prev = old;
 
-	if (!evlist->overwrite)
-		perf_mmap__write_tail(md, old);
-
 	return event;
 }
 
+void perf_evlist__mmap_consume(struct perf_evlist *evlist, int idx)
+{
+	if (!evlist->overwrite) {
+		struct perf_mmap *md = &evlist->mmap[idx];
+		unsigned int old = md->prev;
+
+		perf_mmap__write_tail(md, old);
+	}
+}
+
 static void __perf_evlist__munmap(struct perf_evlist *evlist, int idx)
 {
 	if (evlist->mmap[idx].base != NULL) {
@@ -563,11 +588,13 @@ void perf_evlist__munmap(struct perf_evlist *evlist)
 {
 	int i;
 
+	if (evlist->mmap == NULL)
+		return;
+
 	for (i = 0; i < evlist->nr_mmaps; i++)
 		__perf_evlist__munmap(evlist, i);
 
-	free(evlist->mmap);
-	evlist->mmap = NULL;
+	zfree(&evlist->mmap);
 }
 
 static int perf_evlist__alloc_mmap(struct perf_evlist *evlist)
@@ -587,6 +614,8 @@ static int __perf_evlist__mmap(struct perf_evlist *evlist,
 	evlist->mmap[idx].base = mmap(NULL, evlist->mmap_len, prot,
 				      MAP_SHARED, fd, 0);
 	if (evlist->mmap[idx].base == MAP_FAILED) {
+		pr_debug2("failed to mmap perf event ring buffer, error %d\n",
+			  errno);
 		evlist->mmap[idx].base = NULL;
 		return -1;
 	}
@@ -595,9 +624,36 @@ static int __perf_evlist__mmap(struct perf_evlist *evlist,
 	return 0;
 }
 
-static int perf_evlist__mmap_per_cpu(struct perf_evlist *evlist, int prot, int mask)
+static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx,
+				       int prot, int mask, int cpu, int thread,
+				       int *output)
 {
 	struct perf_evsel *evsel;
+
+	evlist__for_each(evlist, evsel) {
+		int fd = FD(evsel, cpu, thread);
+
+		if (*output == -1) {
+			*output = fd;
+			if (__perf_evlist__mmap(evlist, idx, prot, mask,
+						*output) < 0)
+				return -1;
+		} else {
+			if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, *output) != 0)
+				return -1;
+		}
+
+		if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
+		    perf_evlist__id_add_fd(evlist, evsel, cpu, thread, fd) < 0)
+			return -1;
+	}
+
+	return 0;
+}
+
+static int perf_evlist__mmap_per_cpu(struct perf_evlist *evlist, int prot,
+				     int mask)
+{
 	int cpu, thread;
 	int nr_cpus = cpu_map__nr(evlist->cpus);
 	int nr_threads = thread_map__nr(evlist->threads);
@@ -607,23 +663,9 @@ static int perf_evlist__mmap_per_cpu(struct perf_evlist *evlist, int prot, int m
 		int output = -1;
 
 		for (thread = 0; thread < nr_threads; thread++) {
-			list_for_each_entry(evsel, &evlist->entries, node) {
-				int fd = FD(evsel, cpu, thread);
-
-				if (output == -1) {
-					output = fd;
-					if (__perf_evlist__mmap(evlist, cpu,
-								prot, mask, output) < 0)
-						goto out_unmap;
-				} else {
-					if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, output) != 0)
-						goto out_unmap;
-				}
-
-				if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
-				    perf_evlist__id_add_fd(evlist, evsel, cpu, thread, fd) < 0)
-					goto out_unmap;
-			}
+			if (perf_evlist__mmap_per_evsel(evlist, cpu, prot, mask,
+							cpu, thread, &output))
+				goto out_unmap;
 		}
 	}
 
@@ -635,9 +677,9 @@ out_unmap:
 	return -1;
 }
 
-static int perf_evlist__mmap_per_thread(struct perf_evlist *evlist, int prot, int mask)
+static int perf_evlist__mmap_per_thread(struct perf_evlist *evlist, int prot,
+					int mask)
 {
-	struct perf_evsel *evsel;
 	int thread;
 	int nr_threads = thread_map__nr(evlist->threads);
 
@@ -645,23 +687,9 @@ static int perf_evlist__mmap_per_thread(struct perf_evlist *evlist, int prot, in
 	for (thread = 0; thread < nr_threads; thread++) {
 		int output = -1;
 
-		list_for_each_entry(evsel, &evlist->entries, node) {
-			int fd = FD(evsel, 0, thread);
-
-			if (output == -1) {
-				output = fd;
-				if (__perf_evlist__mmap(evlist, thread,
-							prot, mask, output) < 0)
-					goto out_unmap;
-			} else {
-				if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, output) != 0)
-					goto out_unmap;
-			}
-
-			if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
-			    perf_evlist__id_add_fd(evlist, evsel, 0, thread, fd) < 0)
-				goto out_unmap;
-		}
+		if (perf_evlist__mmap_per_evsel(evlist, thread, prot, mask, 0,
+						thread, &output))
+			goto out_unmap;
 	}
 
 	return 0;
@@ -672,20 +700,92 @@ out_unmap:
 	return -1;
 }
 
-/** perf_evlist__mmap - Create per cpu maps to receive events
- *
- * @evlist - list of events
- * @pages - map length in pages
- * @overwrite - overwrite older events?
- *
- * If overwrite is false the user needs to signal event consuption using:
- *
- *	struct perf_mmap *m = &evlist->mmap[cpu];
- *	unsigned int head = perf_mmap__read_head(m);
+static size_t perf_evlist__mmap_size(unsigned long pages)
+{
+	/* 512 kiB: default amount of unprivileged mlocked memory */
+	if (pages == UINT_MAX)
+		pages = (512 * 1024) / page_size;
+	else if (!is_power_of_2(pages))
+		return 0;
+
+	return (pages + 1) * page_size;
+}
+
+static long parse_pages_arg(const char *str, unsigned long min,
+			    unsigned long max)
+{
+	unsigned long pages, val;
+	static struct parse_tag tags[] = {
+		{ .tag  = 'B', .mult = 1       },
+		{ .tag  = 'K', .mult = 1 << 10 },
+		{ .tag  = 'M', .mult = 1 << 20 },
+		{ .tag  = 'G', .mult = 1 << 30 },
+		{ .tag  = 0 },
+	};
+
+	if (str == NULL)
+		return -EINVAL;
+
+	val = parse_tag_value(str, tags);
+	if (val != (unsigned long) -1) {
+		/* we got file size value */
+		pages = PERF_ALIGN(val, page_size) / page_size;
+	} else {
+		/* we got pages count value */
+		char *eptr;
+		pages = strtoul(str, &eptr, 10);
+		if (*eptr != '\0')
+			return -EINVAL;
+	}
+
+	if (pages == 0 && min == 0) {
+		/* leave number of pages at 0 */
+	} else if (!is_power_of_2(pages)) {
+		/* round pages up to next power of 2 */
+		pages = next_pow2_l(pages);
+		if (!pages)
+			return -EINVAL;
+		pr_info("rounding mmap pages size to %lu bytes (%lu pages)\n",
+			pages * page_size, pages);
+	}
+
+	if (pages > max)
+		return -EINVAL;
+
+	return pages;
+}
+
+int perf_evlist__parse_mmap_pages(const struct option *opt, const char *str,
+				  int unset __maybe_unused)
+{
+	unsigned int *mmap_pages = opt->value;
+	unsigned long max = UINT_MAX;
+	long pages;
+
+	if (max > SIZE_MAX / page_size)
+		max = SIZE_MAX / page_size;
+
+	pages = parse_pages_arg(str, 1, max);
+	if (pages < 0) {
+		pr_err("Invalid argument for --mmap_pages/-m\n");
+		return -1;
+	}
+
+	*mmap_pages = pages;
+	return 0;
+}
+
+/**
+ * perf_evlist__mmap - Create mmaps to receive events.
+ * @evlist: list of events
+ * @pages: map length in pages
+ * @overwrite: overwrite older events?
  *
- *	perf_mmap__write_tail(m, head)
+ * If @overwrite is %false the user needs to signal event consumption using
+ * perf_mmap__write_tail().  Using perf_evlist__mmap_read() does this
+ * automatically.
  *
- * Using perf_evlist__read_on_cpu does this automatically.
+ * Return: %0 on success, negative error code otherwise.
  */
 int perf_evlist__mmap(struct perf_evlist *evlist, unsigned int pages,
 		      bool overwrite)
@@ -695,14 +795,6 @@ int perf_evlist__mmap(struct perf_evlist *evlist, unsigned int pages,
 	const struct thread_map *threads = evlist->threads;
 	int prot = PROT_READ | (overwrite ? 0 : PROT_WRITE), mask;
 
-        /* 512 kiB: default amount of unprivileged mlocked memory */
-        if (pages == UINT_MAX)
-                pages = (512 * 1024) / page_size;
-	else if (!is_power_of_2(pages))
-		return -EINVAL;
-
-	mask = pages * page_size - 1;
-
 	if (evlist->mmap == NULL && perf_evlist__alloc_mmap(evlist) < 0)
 		return -ENOMEM;
 
@@ -710,9 +802,11 @@ int perf_evlist__mmap(struct perf_evlist *evlist, unsigned int pages,
 		return -ENOMEM;
 
 	evlist->overwrite = overwrite;
-	evlist->mmap_len = (pages + 1) * page_size;
+	evlist->mmap_len = perf_evlist__mmap_size(pages);
+	pr_debug("mmap size %zuB\n", evlist->mmap_len);
+	mask = evlist->mmap_len - page_size - 1;
 
-	list_for_each_entry(evsel, &evlist->entries, node) {
+	evlist__for_each(evlist, evsel) {
 		if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
 		    evsel->sample_id == NULL &&
 		    perf_evsel__alloc_id(evsel, cpu_map__nr(cpus), threads->nr) < 0)
@@ -725,8 +819,7 @@ int perf_evlist__mmap(struct perf_evlist *evlist, unsigned int pages,
 	return perf_evlist__mmap_per_cpu(evlist, prot, mask);
 }
 
-int perf_evlist__create_maps(struct perf_evlist *evlist,
-			     struct perf_target *target)
+int perf_evlist__create_maps(struct perf_evlist *evlist, struct target *target)
 {
 	evlist->threads = thread_map__new_str(target->pid, target->tid,
 					      target->uid);
@@ -734,9 +827,7 @@ int perf_evlist__create_maps(struct perf_evlist *evlist,
 	if (evlist->threads == NULL)
 		return -1;
 
-	if (perf_target__has_task(target))
-		evlist->cpus = cpu_map__dummy_new();
-	else if (!perf_target__has_cpu(target) && !target->uses_mmap)
+	if (target__uses_dummy_map(target))
 		evlist->cpus = cpu_map__dummy_new();
 	else
 		evlist->cpus = cpu_map__new(target->cpu_list);
@@ -751,14 +842,6 @@ out_delete_threads:
 	return -1;
 }
 
-void perf_evlist__delete_maps(struct perf_evlist *evlist)
-{
-	cpu_map__delete(evlist->cpus);
-	thread_map__delete(evlist->threads);
-	evlist->cpus	= NULL;
-	evlist->threads = NULL;
-}
-
 int perf_evlist__apply_filters(struct perf_evlist *evlist)
 {
 	struct perf_evsel *evsel;
@@ -766,7 +849,7 @@ int perf_evlist__apply_filters(struct perf_evlist *evlist)
 	const int ncpus = cpu_map__nr(evlist->cpus),
 		  nthreads = thread_map__nr(evlist->threads);
 
-	list_for_each_entry(evsel, &evlist->entries, node) {
+	evlist__for_each(evlist, evsel) {
 		if (evsel->filter == NULL)
 			continue;
 
@@ -785,7 +868,7 @@ int perf_evlist__set_filter(struct perf_evlist *evlist, const char *filter)
 	const int ncpus = cpu_map__nr(evlist->cpus),
 		  nthreads = thread_map__nr(evlist->threads);
 
-	list_for_each_entry(evsel, &evlist->entries, node) {
+	evlist__for_each(evlist, evsel) {
 		err = perf_evsel__set_filter(evsel, ncpus, nthreads, filter);
 		if (err)
 			break;
@@ -804,7 +887,7 @@ bool perf_evlist__valid_sample_type(struct perf_evlist *evlist)
 	if (evlist->id_pos < 0 || evlist->is_pos < 0)
 		return false;
 
-	list_for_each_entry(pos, &evlist->entries, node) {
+	evlist__for_each(evlist, pos) {
 		if (pos->id_pos != evlist->id_pos ||
 		    pos->is_pos != evlist->is_pos)
 			return false;
@@ -820,7 +903,7 @@ u64 __perf_evlist__combined_sample_type(struct perf_evlist *evlist)
 	if (evlist->combined_sample_type)
 		return evlist->combined_sample_type;
 
-	list_for_each_entry(evsel, &evlist->entries, node)
+	evlist__for_each(evlist, evsel)
 		evlist->combined_sample_type |= evsel->attr.sample_type;
 
 	return evlist->combined_sample_type;
@@ -838,7 +921,7 @@ bool perf_evlist__valid_read_format(struct perf_evlist *evlist)
 	u64 read_format = first->attr.read_format;
 	u64 sample_type = first->attr.sample_type;
 
-	list_for_each_entry_continue(pos, &evlist->entries, node) {
+	evlist__for_each(evlist, pos) {
 		if (read_format != pos->attr.read_format)
 			return false;
 	}
@@ -895,7 +978,7 @@ bool perf_evlist__valid_sample_id_all(struct perf_evlist *evlist)
 {
 	struct perf_evsel *first = perf_evlist__first(evlist), *pos = first;
 
-	list_for_each_entry_continue(pos, &evlist->entries, node) {
+	evlist__for_each_continue(evlist, pos) {
 		if (first->attr.sample_id_all != pos->attr.sample_id_all)
 			return false;
 	}
@@ -920,9 +1003,12 @@ void perf_evlist__close(struct perf_evlist *evlist)
 	struct perf_evsel *evsel;
 	int ncpus = cpu_map__nr(evlist->cpus);
 	int nthreads = thread_map__nr(evlist->threads);
+	int n;
 
-	list_for_each_entry_reverse(evsel, &evlist->entries, node)
-		perf_evsel__close(evsel, ncpus, nthreads);
+	evlist__for_each_reverse(evlist, evsel) {
+		n = evsel->cpus ? evsel->cpus->nr : ncpus;
+		perf_evsel__close(evsel, n, nthreads);
+	}
 }
 
 int perf_evlist__open(struct perf_evlist *evlist)
@@ -932,7 +1018,7 @@ int perf_evlist__open(struct perf_evlist *evlist)
 
 	perf_evlist__update_id_pos(evlist);
 
-	list_for_each_entry(evsel, &evlist->entries, node) {
+	evlist__for_each(evlist, evsel) {
 		err = perf_evsel__open(evsel, evlist->cpus, evlist->threads);
 		if (err < 0)
 			goto out_err;
@@ -945,10 +1031,9 @@ out_err:
 	return err;
 }
 
-int perf_evlist__prepare_workload(struct perf_evlist *evlist,
-				  struct perf_target *target,
+int perf_evlist__prepare_workload(struct perf_evlist *evlist, struct target *target,
 				  const char *argv[], bool pipe_output,
-				  bool want_signal)
+				  void (*exec_error)(int signo, siginfo_t *info, void *ucontext))
 {
 	int child_ready_pipe[2], go_pipe[2];
 	char bf;
@@ -992,13 +1077,26 @@ int perf_evlist__prepare_workload(struct perf_evlist *evlist,
 
 		execvp(argv[0], (char **)argv);
 
-		perror(argv[0]);
-		if (want_signal)
-			kill(getppid(), SIGUSR1);
+		if (exec_error) {
+			union sigval val;
+
+			val.sival_int = errno;
+			if (sigqueue(getppid(), SIGUSR1, val))
+				perror(argv[0]);
+		} else
+			perror(argv[0]);
 		exit(-1);
 	}
 
-	if (perf_target__none(target))
+	if (exec_error) {
+		struct sigaction act = {
+			.sa_flags     = SA_SIGINFO,
+			.sa_sigaction = exec_error,
+		};
+		sigaction(SIGUSR1, &act, NULL);
+	}
+
+	if (target__none(target))
 		evlist->threads->map[0] = evlist->workload.pid;
 
 	close(child_ready_pipe[1]);
@@ -1059,10 +1157,89 @@ size_t perf_evlist__fprintf(struct perf_evlist *evlist, FILE *fp)
 	struct perf_evsel *evsel;
 	size_t printed = 0;
 
-	list_for_each_entry(evsel, &evlist->entries, node) {
+	evlist__for_each(evlist, evsel) {
 		printed += fprintf(fp, "%s%s", evsel->idx ? ", " : "",
 				   perf_evsel__name(evsel));
 	}
 
-	return printed + fprintf(fp, "\n");;
+	return printed + fprintf(fp, "\n");
+}
+
+int perf_evlist__strerror_tp(struct perf_evlist *evlist __maybe_unused,
+			     int err, char *buf, size_t size)
+{
+	char sbuf[128];
+
+	switch (err) {
+	case ENOENT:
+		scnprintf(buf, size, "%s",
+			  "Error:\tUnable to find debugfs\n"
+			  "Hint:\tWas your kernel was compiled with debugfs support?\n"
+			  "Hint:\tIs the debugfs filesystem mounted?\n"
+			  "Hint:\tTry 'sudo mount -t debugfs nodev /sys/kernel/debug'");
+		break;
+	case EACCES:
+		scnprintf(buf, size,
+			  "Error:\tNo permissions to read %s/tracing/events/raw_syscalls\n"
+			  "Hint:\tTry 'sudo mount -o remount,mode=755 %s'\n",
+			  debugfs_mountpoint, debugfs_mountpoint);
+		break;
+	default:
+		scnprintf(buf, size, "%s", strerror_r(err, sbuf, sizeof(sbuf)));
+		break;
+	}
+
+	return 0;
+}
+
+int perf_evlist__strerror_open(struct perf_evlist *evlist __maybe_unused,
+			       int err, char *buf, size_t size)
+{
+	int printed, value;
+	char sbuf[128], *emsg = strerror_r(err, sbuf, sizeof(sbuf));
+
+	switch (err) {
+	case EACCES:
+	case EPERM:
+		printed = scnprintf(buf, size,
+				    "Error:\t%s.\n"
+				    "Hint:\tCheck /proc/sys/kernel/perf_event_paranoid setting.", emsg);
+
+		value = perf_event_paranoid();
+
+		printed += scnprintf(buf + printed, size - printed, "\nHint:\t");
+
+		if (value >= 2) {
+			printed += scnprintf(buf + printed, size - printed,
+					     "For your workloads it needs to be <= 1\nHint:\t");
+		}
+		printed += scnprintf(buf + printed, size - printed,
+				     "For system wide tracing it needs to be set to -1");
+
+		printed += scnprintf(buf + printed, size - printed,
+				    ".\nHint:\tThe current value is %d.", value);
+		break;
+	default:
+		scnprintf(buf, size, "%s", emsg);
+		break;
+	}
+
+	return 0;
+}
+
+void perf_evlist__to_front(struct perf_evlist *evlist,
+			   struct perf_evsel *move_evsel)
+{
+	struct perf_evsel *evsel, *n;
+	LIST_HEAD(move);
+
+	if (move_evsel == perf_evlist__first(evlist))
+		return;
+
+	evlist__for_each_safe(evlist, n, evsel) {
+		if (evsel->leader == move_evsel->leader)
+			list_move_tail(&evsel->node, &move);
+	}
+
+	list_splice(&move, &evlist->entries);
 }